CPUCTL(8)						    BSD System Manager's Manual 						 CPUCTL(8)

NAME

     cpuctl -- program to control CPUs

SYNOPSIS

     cpuctl command [arguments]

DESCRIPTION

     The cpuctl command can be used to control and inspect the state of CPUs in the system.

     The first argument, command, specifies the action to take.  Valid commands are:

     identify cpu     Output information on the specified CPU's features and capabilities.  Not available on all architectures.

     list	      For each CPU in the system, display the current state and time of the last state change.

     offline cpuno    Set the specified CPU off line.

		      Unbound LWPs (lightweight processes) will not be executed on the CPU while it is off line.  Bound LWPs will continue to be
		      executed on the CPU, and device interrupts routed to the CPU will continue to be handled.  A future release of the system
		      may allow device interrupts to be re-routed away from individual CPUs.

		      At least one CPU in the system must remain on line.

     online cpuno     Set the specified CPU on line, making it available to run unbound LWPs.

     ucode [file]     This applies the microcode patch on all CPUs.  The default filename is used if no filename is specified.	The identify com-
		      mand prints the installed version on that CPU.  On success the identify command show different ucode versions before and
		      after this command.

FILES

     /dev/cpuctl  control device
     /libdata/firmware/x86/amd/
		  The directory to install the microcode file for AMD CPUs into.  The default filename is microcode_amd.bin for CPU families 0x10
		  to 0x14.  The default filename is microcode_amd_famXXh.bin where XX is the CPU family starting with 15 (hex).  Get it from
		  http://www.amd64.org/support/microcode.html

EXAMPLES

     Run
	   cpuctl identify 0
     and you should see something like this:

	   cpu0: UCode version: 0x1000080

     After applying the microcode patch with
	   cpuctl ucode
     you can see with
	   cpuctl identify 0
     that the patch got applied:

	   cpu0: UCode version: 0x1000083

SEE ALSO

     psrset(8), schedctl(8)

HISTORY

     The cpuctl command first appeared in NetBSD 5.0.

BSD
								 January 13, 2012							       BSD